-
427 BCE
Plato
atoms of matter must derive from these five fundamental solids -
400 BCE
Democritus
that atoms are indestructible, and have always been and always will be in motion -
322 BCE
Aristotle
He held that matter was fundamentally constructed out of atoms. -
400
The Alchemist
They were trying to turn lead into gold. It took many centuries for this concept of the chemical elements to evolve. -
Robert Boyle
He discovered the volume of a gas decreases with increasing pressure and vice versa. -
Lavoisier
the total mass of products and reactants in a chemical reactions is always the same. This led to the theory of the law of conservation of mass. -
John Dalton
He thought atoms were the smallest particles of matter, he envisioned them as solid, hard spheres, like billiard -
Dmitri Mendeleev
Russian chemist who devised the periodic table of the elements -
Photoelectric Effect
process where by the energy from electromagnetic radiation, such as visible light, gamma radiation or other, hits an atomic electron whereby the energy of the radiation is transferred in its entirety to the electron causing the electron to be ejected from the atom. -
J.J Thomson
credited with the discovery of the electron, and he also came up with a thing call the "Plum Pudding" Model -
Plank's Quantum Theory Of light
the energy of light is proportional to the frequency -
Albert Einstein
He is best known for his equation E = mc2, which states that energy and mass -
The Curies
They were the chemist who conducted pioneering research on radioactivity. -
Robert Millikan
precisely determining the magnitude of the electron's charge -
Ernest Rutherford
The discovered that the atom is mostly empty space -
Neils Bohr
He discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determines the properties of an element. -
Henry G.J. Mosely
English physicist who experimentally demonstrated that the major properties of an element are determined by the atomic number -
Schrodinger Equation
to find the allowed energy levels of quantum mechanical systems -
Werner Heisenberg
states that a particle's position and momentum cannot both be known exactly known. -
James chadwick
bombarded beryllium atoms with alpha particles. An unknown radiation was made